Intaglio-printing machine



M. owEN INTAGLIO PRINTING MACHINE Filed July 9, 1923 2 Sheets-Sheet l May 26, 1925. 1,539,202

- M. OWEN INTAGLIO PRINTING MACHINE Filed July 9, 1.925 2 Sheets-Sheet 2 Mum ram /7. 014/5.

Patented May 26, 1925.

UNITED STATES MALCOLM OWEN, OF LONDON, ENGLAND.

INTAGLIOPRINTING MACHINE.

Application filed July 9,

To ail el /mm it may concern:

Be it known that I, MALCOLM OWEN, a subject of the King of Great Britain. residing at 109 Farringdon Road, London, E. C. 1, England, have invented certain new and useful Improvements in Intaglio-PrintinglVfa chines, of which the following is a spec1fication.

This invention relates to doctor operating gear for wiping ink from sheets on printlng cylinders having a gap in which the ends of a printing sheet are fastened, and has-for its object to provide a construction wherein the lift of the doctor may be varied according to the speed of the cylinder; when the speed of the cylinder is increased it becomes necessary to advance the lifting operation because a certain amount of time is taken up in completing the lifting movement, during which the doctor straightens outv from the flexed position when wiping, and this must be accomplished before the gap passes under the doctor; otherwise chattering would occur.

Another object is to vary the pressure of the doctor on the cylinder during wiping operations.

Further objects are to simplify the construction of doctor operating gear, to provide a construction wherein the lift of the doctor may be maintained for variable periods, and to provide a simple cam construction having a variable effective surface to vary the maintained lift of a doctor.

Preferred constructions of the invention are shown by way of example in the accompanying drawings, in which:

- Fig. 1 is a side elevation on the line 1-1 of Fig. 2;

Fig. 2 is a plan showing the arrangement ofa cam lever and doctor in relation to a printing cylinder having a cam on its shaft for operating the lever; i

Fig. 3 is a similar view to Fig. 1 of a modified construction, wherein the operating cam is fixed on the axle of the impression cylinder; and

Fig, 4 is a side elevation to an enlarged scale of the operating cam illustrated in Fig. 3.

Referring to these drawings, 1 is the printing cylinder-having a printing sheet wrapped around it, thelends of the sheet being fastened in known manner in the gap 2. The doctor indicated by the reference 3 is carried 1n usual manner on a bracket 1923. Serial No. 650,458.

4 on the square part 5 of a shaft 6 arranged parallel to the printing cylinder and is rotatably carried in suitable hearings in the side frames of the machine, axial movement being prevented by collars, such as 42, removably fixed by pins 43 to the shaft 6. As both ends of the shaft 6 are similarly supported only one end of such shaft is shown (Fig. 2). In 2 the frame of the machine is indicated by the reference 7. The screw 8 is for adjusting the position of. the doctor on its bracket 4.

In order to keep the doctor 3 pressing on to the printing surface of the cylinder 1, the shaft 6 is provided at one end with a lever 9 which is fixed to the shaft, the lever 9 carrying at its free end a weight 10. which tending to fall, tendsalso'to rotate the shaft 6 through the agency of the lever 9 and therebv to press the doctor on to the print ing cylinder.

Supported in the side frame 7 of the machine and slightly below the shaft 6 is a parallel rod 11 carrying near the frame 7 two fixed spaced flanges 12. between which is located a hollow boss 13,0f a lever 14 carrying at its free end a roller 15 adjustable longitudinally of the lever by reason of its axis pin 16 being adjustably fixed in a slot 17 formed in the said free end. On the axle 18 of the printing cylinder l is arranged a cam 19, beneath the roller 15, which as the cylinder rotates, passes under the roller 15, thereby imparting an upward movement in the lever 14 about the rod 11. The

cam is disposed so that when the lift in the lever is transmitted to the doctor, the doct-or is lifted just before the gap 2 of the cylinder passes thereunder and is maintained lifted until the gap has completely passed the edge of the doctor. To this end the lever 14 is provided intermediately between its roller and boss 13 with a platform 20-, which transmits the lift through an adjustable distance piece 21 carried at the respective side of the doctor by a bracket 40 fixed. on the shaft 6 and ovcrthe lever 14.

By providing the distance piece 21 as an adjustable member it is possible to vary the effect of the Weight 10 on the doctor, and aceordingly to vary the time taken to complete the lift of the doctor from the cylinder;

the nut- 41 acts as a lock nut on the member 21.

The operation in each succession revolution of the printing cylinder is the same, as

the cam, being fixed to the axle 18, moves synchronously with the cylinder.

,In Fig. 2 the reference 22 indicates the cap of a plummer block securing the axle 18 in the side frames isrequired and the timing according to the I speed is attained by moving the axis pin 16 in the slot 17.

Referring now to Figs. 3 and 4, the printing cylinder 1 is shown to be in peripheral contact with an impression cylinder 23, the latter having an effective diameter of twice the diameter of the printing cylinder. It will be seen therefore that. for every revolution of the cylinder 23 there will be two of the cylinder 1.

The impression cylinder 23 is covered by the usual rubber sheet indicated at 24, to an extent equal .to the circumference of thecylinder 1, and is fixed in'usual manner in recesses in the cylinder; the reference 26 indicates the usual gripper for carrying the printing paper.

The face 25 of the cylinder is set back from the periphery of the sheet 24, and

with such an arrangement the peripheral contact between the cylinders 1 and 23 is only maintained during alternate revolutions of the cylinder 1, and in the intermediaterevolutions the periods of peripheral contact are interrupted, the cylinder 1 being juxtaposedto the set back face 25 of the cylinder 23.

While the-cylinders arefin peripheral contact a printing operation is performed, and in the intermediate periods a new sheet is taken by the grippers 26 in known manner and fed round to'the printing area In the construction shown in Figs. 3 and 4 the cam operating the 1 lever controlling the lift of the doctor is indicated at 27, and the lever 14 is, as before, at right angles to the printing and impression cylinders, but is somewhat'longer so as to extend from the rod 11 to the axle 28*of the impression cylinder.

The operating cam 27 has an effective-surface suflicient to lift the doctor 3 off the cylinderl for the non-printing revolution plus the width .of 'the gap 2,. and in addition to providing the adjustable roller 15 the cam 27 is extensible so that its effective surface can be regulated in order to provide adjustment when a new doctor is employed or a doctor of different flexibility. To this end the cam 27 is provided with an. adjustable extension 29 mounted on a slotted angle plate 30 fixed to the axle 28 by a screw bolt 31 taking into the said axle, the extension 29 being preferably slotted to form a guide for. a pin 32 carried by the juxtaposed side of the cam 20, which latter is rigidly fixed on the axle 28 by means of a plate 33 and bolt 34.

The operation of the construction shown in Figs. 3 and 4 is similar to that described in Figs. 1 and 2, viz, the lever 14 at the side .of the printing and impression cylinders is lifted asthe operating cam passes under the roller 15, the lift being transmitted through the distance piece 21 and the brackets 4 and 40 to the doctor, effecting a corresponding lift in the doctor, the same operation occurring at each revolution of the printing cylinder, and therefore at the specified times with regard to the printing cylinder, as the cam, being fixed on the axle 28, moves synchronously with the printing cylinder.

It should here be explained that in referring to the lift of the doctor it is not entirely removed from the printing cylinder 1 during the non-printing operation because, of course, ink would otherwise fly round with the cylinder. In the lifted position the doctor just wipes the cylinder 1 to remove the ink.

I am aware that in conjunction with a cylinder carrying on its surface printing blocks removably fitted thereto for printing, it has heretofore been proposed to provide a rocker shaft carrying a doctor with a lever. at the free end of which a roller is mounted to ride on a cam coaxial with the cylinder, the cam being designed to lift the doctor clear of the cylinder when the blocks are not passing under the doctor, the free end of the lever being slotted so that the roller could be adjusted to the cam after the doctor has been set to each printing surface, the effective radius of which changes practically each time a change of blocks occurs, and I make no claim to the novelty of such construction, but- I claim: 7

1. In combination, a printing cylinder having a gap inwhich the ends of a printing sheet are fastened. a rocking shaft, a doctor mounted on said shaft, a cam rotat ing synchronously with theprinting cylinder, a lever rocked by said cam, adjustable means imparting the movement of said lever to said doctor,.whereby the pressure of the doctor on the cylinder may be varied, and a roller adjustably mounted for longitudinal movement on that end of the lever operated by said cam, whereby the lift of I i the doctor effected through 'said lever can be timed to suit the speed of the cylinder.

2. In combination, a printing cylinder having a gap in which the ends of a printing sheet are fastened, a rocking shaft, a doctor mounted on said shaft, a cam rotating synchronously with the printing cylinder, a lever rocked by said vcam, a platform on said lever, an adjustable distance piece between said doctor and platform for imparting the movement of said lever to said doctor, whereby' the pressure of the doctor on the cylinder may be varied, and a roller adjustably mounted for longitudinal movement on that end of the lever operated by said cam, whereby the lift of the doctor effected through said lever can be timedto suit the speed of the cylinder.

3. In combination, a printing cylinder having a gap in which the'ends of a printing sheet are fastened, a rocking shaft, a doctor mounted on said shaft, a bracket fixed on said shaft, an adjustable distance piece carried by said bracket, a lever, a platform on said lever engaging said distance piece, a roller carried on the free end of said lever for adjustment longitudinally thereof, a cam rotating synchronously with the printing cylinder and cooperating with the roller to lift said lever, and thereby through said platform and adjustable distance piece, the doctor.

4. In combination, a printing cylinder having a gap in which the ends of a printing sheet are fastened, a rocking shaft, a doctor mounted on said shaft, a bracket fixed on said shaft, an adjustable distance piece carried by said bracket, a lever, a platform on said lever engaging said distance piece, a roller carried on the free end of said lever for adjustment longitudinally thereof, an extensible cam rotating synchronously with the printing cylinder and co-operating with the roller to lift said lever, and thereby through said platform and adjustable distance niece, the doctor.

5. In combination, a printing cylinder, an

impression cylinder in peripheral contact with said printing cylinder, a rocking shaft,

a doctor mounted on said shaft, a bracket a doctor mounted on said shaft, a bracket fixed on said shaft, an adjustable distance piece carried by said bracket, a lever, a platform on said lever engaging said "distance piece, a roller carried on the free end of .said lever for adjustment longitudinally thereof, an extensible cam mounted on the axis of the impression cylinder for rotation therewith and co-operating with the roller to lift said lever, and thereby through said platform and adjustable distance piece, the doctor.

7. In combination, a printing cylinder having a gap in which the ends of a printing sheet are fastened, a parallel impression cylinder twice the diameter of the printing cylinder having an effective circumferential face equal to the circumference of the printing cylinder and a" set back face, so that on alternate revolutions only of the printing cylinder the cylinders are in peripheral contact, a pivoted doctor, disposed to wipe the printing sheet, a lever disposed at right angles to the cylinders, a roller carried on the free end of the lever for adjustment longitudinally on the lever, a cam mounted for rotation with the impression cylinder for operating the lever by engaging the roller, a platform on the lever, and an adjustable distance piece between the platform and the doctor, whereby an upward movement in the lever transmits a lift to the doctor relatively to the printing cylinder, while a descent of thelever permits return of the doctor to initial position.

8. In combination, a printing cylinder having a gap in which the ends of a printing sheet are fastened, a parallel impression cylinder twice the diameter of the printing cylinder having an effective circumferential face equal to the circumference of the printillg cylinder and a set back face, so that on alternate revolutions only of the printing cylinder, the cylinders are in peripheral contact, a pivoted doctor, disposed to wipe the printing sheet, a lever disposed at rightangles to the cylinders, a roller carried on the free end of the lever for adjustment longitudinally on the lever, an extensible cam rotating with the impression cylinder for operating the lever by engaging the roller,

a platform on the lever, and an adjustable distance piece between the platform and the doctor, whereby an upward movement in the lever transmits a lift to the doctor relatively to the printing cylinder, while a descent of the lever permits return of the doctor to initial position.

In testimony whereof I affix my signature.

MALCOLM OWEN. 

